ICHTHYOLOGY. 7 



and, 6. The Chrondropterygious have their gills 

 cartilaginous, or of a gristly substance. 



Q. Is there not a more simple division than 

 this ? 



A. Yes ; Fish are divided into cetaceous, carti- 

 laginous, and spinous ; all of which differ in their 

 appearance, conformation, and habits. 



CHAPTER II. 



Of Cetaceous Fish. 



Q. WHAT is meant by Cetaceous Fish, and 

 how are they distinguished ? 



A. Cetaceous fish are those of the Whale kind *, 

 which, from their peculiar characteristics, have 

 been classed by Linnaeus, among terrestrial ani- 

 mals of the class Mammalia f. 



Q. Describe them. 



A. They breathe by means of lungs, have their 

 stomach and intestines like those of quadrupeds, 

 and their eyes defended by lids ; they bring forth 

 their young alive and suckle them, and they 



* From cete, a whale. 



t Those that suckle their youna^. 



